wip_dir Context Manager Rename Retry

[TManzini]

This fix will attempt to rename the temporary folder for 10sec. This is due to an issue on windows machines that causes the renaming of the temporary folder to result in a PermissionError for several seconds after the last image is written.

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[ptpt]

Thanks for the PR @TManzini

Could you provide more context on the permission issue (e.g. any links)?

[TManzini]

Sure, unfortunately the details around this behavior are poorly documented, but here is the trail that I followed to arrive at the PR.

When running the process_video script I kept getting PermissionError: [WinError 5] Access is denied: <PATH_TO_WIP_DIR> -> <PATH_TO_DONE_DIR>

• I traced this to the rename() call referenced in the PR.
• pathlib.Path.rename() relies on os.rename()
• os.rename() does not have any documentation for PermissionError [WinError 5], likely because it is the result of some os specific function, but it has been observed in a number of places 1, 2.
• Python does not handle edge cases like this as they are considered low level os details that would be too much effort to maintain. The most relevant discussion as it relates to this PR is this thread where a user calls out this specific behavior, and the issue is closed as not a bug because python does not wish to handle the edge case.

So the suggestion is to continuously retry the rename for a certain amount of time until the OS realizes the rename is okay, or it times out. I set 10s as an arbitrary number. This behavior only seems to occur on windows.

[ptpt]

Thanks for the context! Lets narrow the hack to the windows platform only.

[ptpt]

@TManzini If you could sign the CLA above, I'm happy to merge the PR to a branch and I will fix some minor issues there.

[TManzini]

Let me know if you are happy with this implementation